1) Endanger 2) Exist 3) Jeopardise 4) Jeopardize 5) Menace 6) Peril 7) Place in danger 8) Pose a threat to 9) Present a danger to 10) Put at risk 11) Put in danger 12) Put into danger 13) Put on the line 14) Risk 15) Threaten 16) Tie Pauline on a track 17) To place in danger 18) To put in peril or danger 1) Endanger 2) Jeopardise 3) Jeopardize 4) Menace 5) Risk 6) Threaten 
• (v. t.) To bring into peril; to endanger.
Im·per'il transitive verb [ imperfect & past participle Imperiled or Imperilled ; present participle & verbal noun Imperiling or Imperilling .] To bring into peril; to endanger. 
to put in peril or danger; endanger.
pose a threat to; present a danger to pose a threat to; present a danger to pose a threat to; present a danger to[Literary terms] pose a threat to; present a danger to